Lancing devices are used by diabetics for sampling blood to measure the blood-sugar level. Such a lancing device generally comprises a cylindrical housing and a lancet holder reciprocally movable in the housing. A lancet is held in the lancet holder, and then the front end of the housing is pressed onto the skin. Thereafter, the lancet holder is advanced to pierce the skin by the needle of the lancet. In this way, the skin bleeds and blood can be sampled.
A conventional lancet, disclosed in JP-A-H6-133955, is shown in FIG. 18A. The illustrated lancet 9 includes a metal needle 91 which is supported by a body 90 made of synthetic resin. The body 90 is integrally formed by resin molding with a cap 92 for covering a tip end of the needle 91. The boundary 93 between the cap 92 and the body 90 is a narrow portion.
The needle 91 of the lancet 9 is covered by the cap 92, so that the needle 91 unused is kept clean. The cap 92 is twisted to break the boundary 93 to detach the cap 92 and the body 90, as shown in FIG. 18B, thereby exposing the tip end of the needle 91.
However, in the prior art, the setting of the lancet 9 to the lancing device is performed after the cap 92 is detached from the lancet 9, in a manner such that the separated lancet 9 is attached to a lancet holder of the lancing device. In this way, unfavorably, the exposed needle 91 of the lancet 9 may prick a finger of the user during the setting operation.
A solution to this problem may be detaching the cap 92 from the lancet 9 after the lancet 9 is attached to the lancet holder of the lancing device. However, even in this manner, the user still needs to pinch the cap 92 and twist it for breaking the boundary 93. Unfavorably, this task is troublesome. Moreover, a typical lancet-setting operation with respect to a lancing device may entail appropriate pushing of the lancet or lancet holder into the housing of the lancing device. In such a case, the setting of the lancet 9 can be more troublesome.